Cartridge fuse



Sept. 9, 1947.

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E. w. WELLS 2,427,245

CARTRIDGE FUSE Filed oct. :51, 1945 JNVENToR. mu M h/c/Ls Patented Sept. 9, 1947 UNITED STATES PATENT OFFICE 1 Claim.

My invention relates to a new and useful improvement in a fuse and has for its object the provision of a renewable fuse which will be simple in structure, economical of manufacture, durable, compact, easily and quickly assembled and highly efficient in use.

Another object of the invention is the provision of a renewable fuse so constructed and arranged that it is ventilated while in use and thus excessive heating of the fuse plug is avoided.

Another object of the invention is the provision of a renewable fuse so constructed and arranged that heat generated within the plug may escape while at the same time the passage of a ame from within the plug is prevented.

Another object of the invention is the provision of a renewable fuse which may be easily and quickly taken apart in order to replace the fusible material.

Another object of the invention is the provision of a renewable fuse having an enclosing housing which may be taken apart and easily and quickly placed together and locked in operative position.

Other objects will appear hereinafter.

It is recognized that various modifications and changes may be made in the detail of structure illustrated and it is intended that such shall be embraced within the scope of the claims which form a part of this application.

Forming a part of this application are drawings in which:

Fig. 1 is a longitudinal central sectional view of the invention,

Fig. 2 is a longitudinal central vertical sectional view of the invention taken at right angles to that shown in Fig. l',

Fig. 3 is a perspective view of the various parts of the invention in their separated relations,

Fig. 4 is a view taken on line 4-4 of Fig. 1,

Fig. 5 is a sectional view taken on line 5-5 of Fig. 1,

Fig. 6 is a longitudinal central sectional view showing a modication,

Fig. '7 is a sectional View taken on line 1-'I of Fig. 6,

Fig. 8 is a fragmentary central vertical sectional view showing the invention modified for use on a ferrule type fuse,

Fig. 9 is a fragmentary central vertical sectional view of form shown in Fig. 8 illustrating the opposite end of fuse.

Forming a part of the enclosing housing is a cylindrical tube or barrel I2 on one end of which is xedly attached a ferrule or a metallic cap I3 having a central circular opening III formed therein radiating outwardly from which at diametrically opposite points are the slots I5. A retaining or supporting body I6 of suitable insulating material is adapted to be enclosed by the tube or barrel I2 which is also made from suitable insulating material. A contact plate I'I is provided with the reduced portion or neck 33 which is projected through the opening 34 formed in the end block 35 of the supporting member IS. Embedded in the member I6 is a nut-forming member 44. A bolt I8 is projected through the neck 33 and threaded into the nut-forming member 44. A spring washer I9 is positioned under the head of the bolt. This bolt I8 also projects through the terminal portion of the fuse strip 24 and through a retaining clip 45 so that when the bolt I8 is tightened the retaining clip 45 will press the end of the fuse strip 24 into close engagement with the reduced portion 33 of the contact plate I'I. Threaded into a similar nut-forming member 44A is a bolt 22 beneath the head of which is positioned a spring washer 23. This bolt 22 also projects through a retaining clip 45, the terminal portion of the fuse strip `24 and the reduced neck 36 of a contact plate ZI so that the two contact plates 2I and I I are thus electrically connected to the fuse strip 24. Positioned beneath the fuse strip 24 is a recess 20 which is formed in the supporting member I6. The neck 36 projects through a suitable slot formed in the end block 31 of the supporting member I6. The ferrule or metallic cap is secured to the end block 3l by means of the screws 38.

Formed in the periphery of the barrel or tube I2 is a groove 30 communicating through the openings 3l, which are preferably diametrically opposite each other, with the interior of the tube or barrel I2. This peripheral groove 30 is covered by the cap or ferrule I3 and formed in the covering portion of the ferrule are openings 32, which are preferably diametrically opposite each other and rotated degrees to the opening 3l. These openings 32 are in registration with the peripheral groove 3Q. Fixedly mounted on the tube or barrel I2 is a metallic ring 26 which serves to cover the peripheral groove 21 formed on the barrel or tube I 2. Openings 28, which are also preferably diametrically opposite each other serve to establish communication of this groove 21 with the interior of the tube or barrel I2. Openings 29, which are preferably diametrically .opposite each other and rotated 90 degrees to the location of the openings `28A are formed in the ring 2S and are in registration with the groove 21. Thus the interior of the fuse plug when assembled as shown in Fig. 1 is always in communication with the atmosphere. This would permit heat generated within the housing to escape through the openings and grooves so that the fuse would be prevented from excessive heating. When a ash occurs and a flame develops within the housing this flame would be prevented from escaping as after passing through the openings 28 or 3i the flame would have to travel around the peripheral groove at least a quarter revolution and in the restricted space the flame would become extinguished.

In order to assemble the structures a simple operation is necessary. The contacts 2l and i1 would be connected together with the fuse stripI 24 and the supporting member l5 as shown in Fig. 1. And in this position the housing may then be slipped over so as to cover the parts and in doing so it is necessary to rotate the tube or barrel l2 until the slots l register with the contact plate I1. When in this position the barrel or tube l2 may be slid onto the assembled structure into the position shown in Fig. 1. By yrotating the tube l2 90 degrees the end wall of the ferrule or cap I3 rideshehind the contact plate i1 and the member l2 is thus locked in position. Conseouently, in order to gain access to the interior of the fuse it would be but necessary to rotate the tube or barrel l2 90 degrees in either direction from the position shown in Fig. 4 whereupon, the tube or barrel I2 could be'moved axially or of the structure. When the covering tube or barrel i2 is removed access to the-fuse strip is of course afforded and an easy and quick replacement of the fuse stripI may be made when necessary.

In-Fig. 6 I have shown a Yslight modication of the structure. This modification however, relates only to the method of attaching the fuse strip 39. This `fuse strip is provided with a slot 40 `in one end to provide a bifurcated structure which may engage around and under the head of the bolt 62. The opposite end of the fuse strip is provided with a hook which may engage around and under the head of the bolt 43. With this structure it would not be necessary to remove the bolt entirely when replacing a fuse strip.

In Fig. 8 and Fig. 9 I have shown a further modification in which the invention may be utilized in connection with a ferrule type fuse. In this structure I utilize a housing or tubular en-v closure 12A corresponding to the part l2 shown in Fig. 1. The supporting body 16A is provided at its end with a projection 31A and at its opposite end with the projection 35A.. Embracing one end of the tubular housing 82A is a metallic ierrule 1l having the inward projection 12 embedded in the housing 12A so that these parts are in iixed relation. This ferrule or cap 1| is provided with the outwardly projecting internally threaded neck 13 which is adapted to thread upon the threaded stud 14 projecting outwardly from the metal plate 15 which is held in position by the bolt 16 which serves to clamp the fuse strip 21A against the part 15. At the opposite end I provide a cap or ferrule 11 having an opening 18 formed centrally therein through which the reduced portion 19 extending outwardly from the plate 8| projects. This reduced portion is upset to provide the Vhead 8S. The. plate 8| is held in clamping relation to the fuse strip 21A by the bolt 82. With this type of fuse the contacts are of course made at the ferrule ends ferrules 1l and 11 contacting spring retainers in a manner which is well known. In order to dis-assemble the structure it is but necessary to grip the ferrule 11 in the hand and then rotate the housing I2A until the neck 13 dis-engages from the theaded stud 14 whereupon the housing 12A may be Withdrawn to allow ready access to the renewable vfuse strip.

With a fuse constructed in this manner a highly eicient apparatus is aiforded and one which will not develop excessive heat and which on account of remaining cool will be of longer life. It is believed obvious that the structure is such that assembling may be easily and quickly effected and that a fuse strip may be removed and replaced with ease.

What I claim as new is:

A fuse of the class described, comprising: a supporting member of insulating material having a recess formed therein intermediate its ends; a Contact plate secured to each end of said supporting member and projecting outwardly therefrom, each of said Contact plates being narrowed intermediate its ends to provide a narrow neck; a fusible fuse strip connecting the inner ends of said Contact plates electrically and spanning said recess; a tubular housing for enclosing said supporting member and said fusible strip and provided with a peripheral groove communicating through an opening with the interior of said housing; a cup-shaped closure for one end of said housing and adapted for embracing the same, said closure having in its side wall an opening registerin T with said groove and out of alignment with the opening through said housing, said cup-shaped closure having a central opening formed in its base suiiiciently large for receiving said neck and provided with radially projected slots extending outwardly therefrom diametrically opposite each other sufficient for passage of the outer end of the contact plate therethrough, relative rotation of said Contact plate and said closure etlecting a movement of said contact plate out of alignment with said radially outwardly projecting slots for securing said closure in position on said tubular housinr and retaining the opening in said closure out of registration with the opening in said tubular housing and preventing axial movement of said tubular housing relatively to said supporting member.

EARL W. WELLS.

REFERENCES CITED rihe following references are of record in the nie ci this patent:

UNITED STATES PATENTS Number Name Date 1,846,660 Rumble Feb. 23, 1932 1,819,293 Hickey Aug. 18, 1931 1,773,184.- Hicliey Aug. 19, 1930 1,396,357 Clemens Nov. 8, 1921 FOREIGN PATENTS Number Country Date 156,494 Great Britain Dec. 29, 1921 

